Unreal Engine Issues

Mac Intel - Sun light is exploding in the viewport

During SIE (simulate) and ejected-PIE, modifying a map actor causes triggers RerunConstructionScript() which discards all runtime modifications to SCS components

When Simulating, or Playing-In-Editor and ejected, modifying an actor in the editor world causes the SIE/PIE runtime actor to recreate its blueprint added components via AActor::RerunConstructionScr ...

Actor blueprint 'bOptimizeBPComponentData' breaks subobject instantiation for runtime spawned actors in cooked builds

A user has reported that when an actor blueprint enables Generate Optimized Component Blueprint Data, default instanced objects of components are not properly duplicated in cooked builds. This resul ...

In some situations, a Blueprint can become devoid of an Event Graph. While no graphs are present, multiple variables can be created with the same name.

In some situations, a Blueprint can become devoid of an Event Graph, or be created without one from the start. For example, function "FKismetEditorUtilities::CreateBlueprint()" in UE 5.4 does not ca ...

Regression: "Object Position" node in Light Function materials did not compile up to UE 5.0. Starting with 5.1, it compiles but outputs garbage values

Up to UE 5.0, when the "Object Position" node is used in the Material Editor as part of a material with Light Function domain, attempting to compile the material results in the following error: "[SM ...

Skylight Intensity causes brightness discrepancy between the pathtracer and realtime renderers

In a scene without a sky sphere, increasing the skylight intensity will cause the sky to brighten in the pathtracer. Other renderers do not brighten the sky, and the intensity increase is applied on ...

Data Layer replication bug

The bug is data layer runtime states can get out of sync between a client and a host depending on the initial runtime state of a data layer and the size of the replicated data layer names array. Se ...

Input Mapping Context entries can get into a corrupted state when swapped with another entry that has a Combo Trigger.

This behaviour was working correctly in version 5.3. This issue happens inside an InputMappingContext DataAsset from the EnhancedInput system. We need at least two mappings entries. One of the entri ...

Niagara Fluids Plugin creates a memory reference of any saved level by only being active, before being actually used.

While Niagara Fluids Plugin is active it creates a memory reference of any saved level regardless of being actually used. Simply enabling the plugin shows a memory reference while deleting the level ...

Blueprint compilation resets settings on level-placed actors

Triggering an actor component recompilation resets all the variables to the default state on spawned actors in the level. Users can unintentionally lose property settings on placed actors in a worl ...